[PATCH v6 17/20] reftable: add dump utility

["Han-Wen Nienhuys via GitGitGadget" <gitgitgadget@gmail.com>]

From: Han-Wen Nienhuys <hanwen@google.com>

provide a command-line utility for inspecting individual tables, and
inspecting a complete ref database

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
---
 reftable/dump.c | 212 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 212 insertions(+)
 create mode 100644 reftable/dump.c

diff --git a/reftable/dump.c b/reftable/dump.c
new file mode 100644
index 000000000000..00b444e8c9b8
--- /dev/null
+++ b/reftable/dump.c
@@ -0,0 +1,212 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+#include "reftable.h"
+#include "reftable-tests.h"
+
+static uint32_t hash_id;
+
+static int dump_table(const char *tablename)
+{
+	struct reftable_block_source src = { 0 };
+	int err = reftable_block_source_from_file(&src, tablename);
+	struct reftable_iterator it = { 0 };
+	struct reftable_ref_record ref = { 0 };
+	struct reftable_log_record log = { 0 };
+	struct reftable_reader *r = NULL;
+
+	if (err < 0)
+		return err;
+
+	err = reftable_new_reader(&r, &src, tablename);
+	if (err < 0)
+		return err;
+
+	err = reftable_reader_seek_ref(r, &it, "");
+	if (err < 0) {
+		return err;
+	}
+
+	while (1) {
+		err = reftable_iterator_next_ref(&it, &ref);
+		if (err > 0) {
+			break;
+		}
+		if (err < 0) {
+			return err;
+		}
+		reftable_ref_record_print(&ref, hash_id);
+	}
+	reftable_iterator_destroy(&it);
+	reftable_ref_record_clear(&ref);
+
+	err = reftable_reader_seek_log(r, &it, "");
+	if (err < 0) {
+		return err;
+	}
+	while (1) {
+		err = reftable_iterator_next_log(&it, &log);
+		if (err > 0) {
+			break;
+		}
+		if (err < 0) {
+			return err;
+		}
+		reftable_log_record_print(&log, hash_id);
+	}
+	reftable_iterator_destroy(&it);
+	reftable_log_record_clear(&log);
+
+	reftable_reader_free(r);
+	return 0;
+}
+
+static int compact_stack(const char *stackdir)
+{
+	struct reftable_stack *stack = NULL;
+	struct reftable_write_options cfg = {};
+
+	int err = reftable_new_stack(&stack, stackdir, cfg);
+	if (err < 0)
+		goto done;
+
+	err = reftable_stack_compact_all(stack, NULL);
+	if (err < 0)
+		goto done;
+done:
+	if (stack != NULL) {
+		reftable_stack_destroy(stack);
+	}
+	return err;
+}
+
+static int dump_stack(const char *stackdir)
+{
+	struct reftable_stack *stack = NULL;
+	struct reftable_write_options cfg = {};
+	struct reftable_iterator it = { 0 };
+	struct reftable_ref_record ref = { 0 };
+	struct reftable_log_record log = { 0 };
+	struct reftable_merged_table *merged = NULL;
+
+	int err = reftable_new_stack(&stack, stackdir, cfg);
+	if (err < 0)
+		return err;
+
+	merged = reftable_stack_merged_table(stack);
+
+	err = reftable_merged_table_seek_ref(merged, &it, "");
+	if (err < 0) {
+		return err;
+	}
+
+	while (1) {
+		err = reftable_iterator_next_ref(&it, &ref);
+		if (err > 0) {
+			break;
+		}
+		if (err < 0) {
+			return err;
+		}
+		reftable_ref_record_print(&ref, hash_id);
+	}
+	reftable_iterator_destroy(&it);
+	reftable_ref_record_clear(&ref);
+
+	err = reftable_merged_table_seek_log(merged, &it, "");
+	if (err < 0) {
+		return err;
+	}
+	while (1) {
+		err = reftable_iterator_next_log(&it, &log);
+		if (err > 0) {
+			break;
+		}
+		if (err < 0) {
+			return err;
+		}
+		reftable_log_record_print(&log, hash_id);
+	}
+	reftable_iterator_destroy(&it);
+	reftable_log_record_clear(&log);
+
+	reftable_stack_destroy(stack);
+	return 0;
+}
+
+static void print_help(void)
+{
+	printf("usage: dump [-cst] arg\n\n"
+	       "options: \n"
+	       "  -c compact\n"
+	       "  -t dump table\n"
+	       "  -s dump stack\n"
+	       "  -h this help\n"
+	       "  -2 use SHA256\n"
+	       "\n");
+}
+
+int reftable_dump_main(int argc, char *const *argv)
+{
+	int err = 0;
+	int opt;
+	int opt_dump_table = 0;
+	int opt_dump_stack = 0;
+	int opt_compact = 0;
+	const char *arg = NULL;
+	while ((opt = getopt(argc, argv, "2chts")) != -1) {
+		switch (opt) {
+		case '2':
+			hash_id = 0x73323536;
+			break;
+		case 't':
+			opt_dump_table = 1;
+			break;
+		case 's':
+			opt_dump_stack = 1;
+			break;
+		case 'c':
+			opt_compact = 1;
+			break;
+		case '?':
+		case 'h':
+			print_help();
+			return 2;
+			break;
+		}
+	}
+
+	if (argv[optind] == NULL) {
+		fprintf(stderr, "need argument\n");
+		print_help();
+		return 2;
+	}
+
+	arg = argv[optind];
+
+	if (opt_dump_table) {
+		err = dump_table(arg);
+	} else if (opt_dump_stack) {
+		err = dump_stack(arg);
+	} else if (opt_compact) {
+		err = compact_stack(arg);
+	}
+
+	if (err < 0) {
+		fprintf(stderr, "%s: %s: %s\n", argv[0], arg,
+			reftable_error_str(err));
+		return 1;
+	}
+	return 0;
+}
-- 
gitgitgadget